PHP安全过滤用户输入

    /**
     * 安全过滤函数
     */
    function public_safe_replace($string)
    {
        $string = str_replace("%20","",$string);
        $string = str_replace("%27","",$string);
        $string = str_replace("%2527","",$string);
        $string = str_replace("*","",$string);
        $string = str_replace(""",""",$string);
        $string = str_replace(""","",$string);
        $string = str_replace(""","",$string);
        $string = str_replace(";","",$string);
        $string = str_replace("<","<",$string);
        $string = str_replace(">",">",$string);
        $string = str_replace("{","",$string);
        $string = str_replace("}","",$string);
        return $string;
    }

    /**
    *  重写addslashes函数，增加安全替换
    */
    function my_addslashes($str)
    {
        $str = public_safe_replace($str);
        $str = addslashes($str);
        return $str;
    }

    /**
     * 递归方式的对变量中的特殊字符进行转义
     */
    function addslashes_deep($value)
    {
        if (empty($value)){
            return $value;
        }
        else{
            return is_array($value) ? addslashes_deep($value) : my_addslashes($value);
        }
    }